1. Field of the Invention
The present disclosure generally relates to motion detectors and, more particularly, to an overhead occupancy sensor such as a ceiling-mounted or high bay occupancy sensor.
2. Description of Related Art
Overhead occupancy sensors are lighting control devices used in high mount areas such as commercial and office ceilings, warehouses, aisles, and manufacturing facilities. These types of sensors detect the presence of motion, such as by humans or other objects in a space and, in response to the detection or lack thereof, actuate lighting circuits, turn on or shut oft electrical power, control climate regulation systems, and the like. Due to the specific requirements of this arrangement, industry practice is to use passive infrared technology for sensing motion. Overhead occupancy sensors are often attached directly to a standard lighting fixture, such as the industrial T8 or T5 fluorescent lighting fixtures, LED luminaries, or to an electrical junction box by means of an industry-standard ½ inch conduit knockout port. Typically, this lighting fixture is situated on a raised ceiling, giving the sensor a view of a large area of the monitored space. However, if the sensor lens is not below the body of the lighting fixture, the lighting fixture itself will block at least part of the field of view of the sensor. Therefore, these sensors often include extension adapters designed to allow some flexibility in the positioning of the sensor. In addition, these adapters provide a means of running tine-voltage AC wiring to the sensor device without installing additional electrical conduit. These extension adapters typically provide a certain number of discrete sensor placement positions, which may not always correspond to the desired positioning. It would be advantageous to provide an extension adapter that provides continuous-range motion that allows the sensor to be placed at exactly the desired height.
An infrared (IR) filter, also referred to as an IR blocking filter, can be placed adjacent to the lens of the sensor and is typically used to block infrared light or radiation from a certain part of the space, rendering the sensor insensitive to motion in that area. The shape of the filter, which is generally of a fixed shape, can be used to determine the sensitivity pattern of the sensor, such as an aisle or hallway. While the filter itself may be rotatable, these filters are not re-shapeable. Rather, if a different monitoring arrangement is desired, a filter can be replaced with one of another shape.
Typical sensors can also have a radially-symmetric lens that is paired with a separate IR filter to achieve non-symmetric sensitivity. In some cases, the filter is rotatable, but not re-shapeable.
It would be advantageous to provide an overhead occupancy sensor device that has continuous-range-of-motion positioning and flexible filter arrangements to allow for fine positioning of the sensor device to avoid spurious triggering of the sensor from stray light and to present the optimum field of view to the lens of the sensor to capture activity in a desired area.
Accordingly, it would be desirable to provide an overhead occupancy sensor device that addresses at least some of the problems identified above.